Dual-tone multi-frequency microphone



FIG. 1 is a front, top, and right side perspective view showing our newdesign for a dual-tone multi-frequency microphone;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a rear elevational view thereof; and,

FIG. 4 is a bottom plan view thereof.

The broken lines in FIGS. 2-4 are for illustrative purposes only andform no part of the claimed design.

The ornamental design for a dual-tone multi-frequency microphone, asshown and described.